Double-seat valve.



W. NAOHTIGALL.

DOUBLE SEAT'VALVE. APPLIOATIONIILED 1930.3, 1909.

Patented Aug. 16, 1910.

Trzverz 757? MM 1 ORRIS m; TERS WILHELIII NACHTIGALL, OF LEIPZIG, GERMANY.

DOUBLE-SEAT VALVE.

Specification of Letters Patent.

Application filed December 3, 1909.

Patented Aug. 16, 1910. Serial No. 531,214.

To all whom it may concern:

Be it known that I, WILI-IELM NAGHTI- GALL, a subject of the German Emperor, residing at Leipzig, in Germany, have invented a certain new and useful Improvement in Double-Seat Valves, of which the follow ing is a specification.

In double-seat valves of the type wherein two inter-connected disks or plates control two orifices, and have seats at the circumferences of the said orifices, and wherein one of the plates is elastic or elastically supported to secure tight seating, it may occur from a fault of constructionor wear that the rigid plate is first seated and prevents proper seating of the resilient plate.

The object of the present invention is to remove this disadvantage, and the invention consists in providing means whereby both the plates are elastically thrust against their seats, independently of each other.

Two constructions embodying this improvement are shown in the annexed drawings, in which Figure l is an elevation, partly in section, of one construction, and Fig. 2 a similar view of the other construction.

Referring in the first place to Fig. 1, a and a are the two plates, which are of elastic material and are connected to each other by a tubular piece d having an outward extension e above the plate a. The spindle b, screw-threaded to work in the threaded eye of a cross-head f above the valve, extends into the tubular part d and has a collar located in a cavity h in the outward extension of the said part d. The spindle b has a hand-wheel Z fixed'to its outer end. If

when the valve is closed the plate a is seated before the plate a continued screwing down of the spindle causes the collar to depress the center of the plate at, until the plate a is also seated. If the plate a is seated before the plate a, the spindle depresses the center of the plate a until the plate a is also seated.

In the modification shown in Fig. 2 the plates a and a are rigid, but the tubular piece (Z connecting them is elastically extensible. This extensible piece 6Z1 has a central diaphragm j against which the spindle abuts. If the plate a is first seated the spindle stretches the upper part of the tubular piece 03 until the plate a is also seat ed. If the plate a is first seated the spindle compresses the lower part of the tubular piece al until the plate a is seated.

What I claim as my invention and desire to secure by Letters Patent of the United States is In a double seat valve system the combination of two valve seatings, two valves movable in the same direction for closing or opening respectively, a spindle for moving said valves collectively toward or from the seatings and an elastic device interposed between each of said valves and the spindle for giving independent elasticity to each of the valves.

In witness whereof I have signed this specification in the presence of two witnesses.

WILHELM NACHTIGALL.

Witnesses RUDOLPH FRICKE, WALTER SoHULzE. 

